This just in from ChatGPT: AI warms "Musk one of the biggest mistakes in civilization"

lulu has been mentioned but if you want to send your book to a "vanity press", amazon only accepts http://www.createspace.com/ books. You might also want to look into asking your old publisher if they would allow you to post the pdf of your new book on a website such as http://www.opentextbook.org/ with an appropriate Creative Common license, allowing them to publish the hard copy. (I did, and they were okay with a pdf but not okay with the LaTeX source - so good luck!) I've used createspace.com myself several times. It is, I understand, slightly more complicated than lulu, but they seem to do a good job. For example, you have to provide a non-standard sized 8''x10'' formatted pdf. (This is fairly easy if your text is in LaTeX). The only option I have used is their free option (you can pay to get an upgraded account with certain benefits ...). The only thing you need to pay for is the proof copy, whcih you must order and approve before publication. Then it is goes on sale on createspace.com and amazon.com.

Since you said you're going for a math PhD, my experience (I have a math PhD and switched from Windows to linux years ago for similar reasons) might help. In addition to latex (and kdvi, etc) and python you'll probably want to use SAGE at some point (SAGE = Software for Algebra and Geometry Exploration, sage.scipy.org). SAGE is developed on ubuntu and Macs but works under SUSE and Redhat and probably other flavors of linux. However, it does not work well under VMWare. If you have trouble setting up a dual boot for some reason, you might also consider colinux. My understanding (I've never used it) is that colinux is essentially linux sitting in windows. I've not used it but heard from some people that it is better than cygwin in some ways. Probably if you google colinux, you find more info. Good luck!